actions: materializeIdeaPlanAction + relinkIdeaPlanAction (M12 T-498)

actions/ideas.ts:
- materializeIdeaPlanAction(id):
  - guard: status===PLAN_READY, plan_md present, product linked, demo-403
  - parsePlanMd → 422 with line-info on fail
  - Prisma.\$transaction:
    - SELECT max(code) for PBI/Story/Task within product
    - INSERT PBI with sort_order = lastPbi+1 within priority
    - per story: INSERT (sequential ST-NNN), per task: INSERT (T-N)
    - UPDATE idea SET pbi_id, status=PLANNED
    - INSERT IdeaLog{PLAN_RESULT, metadata}
  - returns 409 on P2002 (concurrent-materialize race)
- relinkIdeaPlanAction(id):
  - guard: status===PLANNED && pbi_id===null (PBI manually deleted via SetNull FK)
  - reverts to PLAN_READY + IdeaLog{NOTE}

Tests: 39 cases total (8 new for materialize + relink): happy creates entities,
status-mismatch-422, parse-fail-422 with details, demo-403, P2002→409,
relink happy + invalid-precondition guards.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

__tests__/actions/ideas-crud.test.ts

@@ -32,6 +32,19 @@ vi.mock('@/lib/prisma', () => ({
     claudeWorker: {
       count: vi.fn(),
     },
+    pbi: {
+      findFirst: vi.fn(),
+      findMany: vi.fn(),
+      create: vi.fn(),
+    },
+    story: {
+      findMany: vi.fn(),
+      create: vi.fn(),
+    },
+    task: {
+      findMany: vi.fn(),
+      create: vi.fn(),
+    },
     $transaction: vi.fn(),
     $executeRaw: vi.fn().mockResolvedValue(0),
   },
@@ -49,6 +62,8 @@ import {
   startGrillJobAction,
   startMakePlanJobAction,
   cancelIdeaJobAction,
+  materializeIdeaPlanAction,
+  relinkIdeaPlanAction,
 } from '@/actions/ideas'
 
 type MockIdea = {
@@ -56,6 +71,9 @@ type MockIdea = {
   ideaLog: { create: ReturnType<typeof vi.fn> }
   claudeJob: { findFirst: ReturnType<typeof vi.fn>; create: ReturnType<typeof vi.fn>; update: ReturnType<typeof vi.fn> }
   claudeWorker: { count: ReturnType<typeof vi.fn> }
+  pbi: { findFirst: ReturnType<typeof vi.fn>; findMany: ReturnType<typeof vi.fn>; create: ReturnType<typeof vi.fn> }
+  story: { findMany: ReturnType<typeof vi.fn>; create: ReturnType<typeof vi.fn> }
+  task: { findMany: ReturnType<typeof vi.fn>; create: ReturnType<typeof vi.fn> }
   $transaction: ReturnType<typeof vi.fn>
   $executeRaw: ReturnType<typeof vi.fn>
 }
@@ -358,6 +376,139 @@ describe('cancelIdeaJobAction', () => {
   })
 })
 
+describe('materializeIdeaPlanAction', () => {
+  const VALID_PLAN = `---
+pbi:
+  title: New PBI
+  priority: 2
+stories:
+  - title: Story A
+    priority: 2
+    tasks:
+      - title: Task A1
+        priority: 2
+        implementation_plan: "1. Doe X"
+      - title: Task A2
+        priority: 2
+  - title: Story B
+    priority: 3
+    tasks:
+      - title: Task B1
+        priority: 3
+---
+
+body
+`
+
+  beforeEach(() => {
+    m.idea.findFirst.mockResolvedValue({
+      id: 'idea-1',
+      status: 'PLAN_READY',
+      product_id: 'prod-1',
+      plan_md: VALID_PLAN,
+    })
+    m.pbi.findMany.mockResolvedValue([])
+    m.story.findMany.mockResolvedValue([])
+    m.task.findMany.mockResolvedValue([])
+    m.pbi.findFirst.mockResolvedValue(null)
+    m.pbi.create.mockResolvedValue({ id: 'pbi-1', code: 'PBI-1' })
+    m.story.create
+      .mockResolvedValueOnce({ id: 's-A' })
+      .mockResolvedValueOnce({ id: 's-B' })
+    m.task.create
+      .mockResolvedValueOnce({ id: 't-A1' })
+      .mockResolvedValueOnce({ id: 't-A2' })
+      .mockResolvedValueOnce({ id: 't-B1' })
+  })
+
+  it('happy: creates PBI + 2 stories + 3 tasks, links idea, returns ids', async () => {
+    const r = await materializeIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({
+      success: true,
+      data: {
+        pbi_id: 'pbi-1',
+        pbi_code: 'PBI-1',
+        story_ids: ['s-A', 's-B'],
+        task_ids: ['t-A1', 't-A2', 't-B1'],
+      },
+    })
+    expect(m.pbi.create).toHaveBeenCalledTimes(1)
+    expect(m.story.create).toHaveBeenCalledTimes(2)
+    expect(m.task.create).toHaveBeenCalledTimes(3)
+  })
+
+  it('blocks when not PLAN_READY (e.g. GRILLED)', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({
+      id: 'idea-1',
+      status: 'GRILLED',
+      product_id: 'prod-1',
+      plan_md: VALID_PLAN,
+    })
+    const r = await materializeIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({ code: 422 })
+    expect(m.pbi.create).not.toHaveBeenCalled()
+  })
+
+  it('returns 422 with details on parse-fail', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({
+      id: 'idea-1',
+      status: 'PLAN_READY',
+      product_id: 'prod-1',
+      plan_md: '# no frontmatter',
+    })
+    const r = await materializeIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({ code: 422 })
+    expect((r as { details?: unknown }).details).toBeDefined()
+  })
+
+  it('blocks demo-user', async () => {
+    mockSession.isDemo = true
+    const r = await materializeIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({ code: 403 })
+  })
+
+  it('returns 409 on P2002 race', async () => {
+    m.$transaction.mockImplementationOnce(async () => {
+      throw new Error('Unique constraint failed (P2002)')
+    })
+    const r = await materializeIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({ code: 409 })
+  })
+})
+
+describe('relinkIdeaPlanAction', () => {
+  it('happy: PLANNED with pbi_id=null → PLAN_READY', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({
+      id: 'idea-1',
+      status: 'PLANNED',
+      pbi_id: null,
+    })
+    const r = await relinkIdeaPlanAction('idea-1')
+    expect(r).toEqual({ success: true })
+    expect(m.$transaction).toHaveBeenCalled()
+  })
+
+  it('blocks when pbi still linked', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({
+      id: 'idea-1',
+      status: 'PLANNED',
+      pbi_id: 'pbi-1',
+    })
+    const r = await relinkIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({ code: 422 })
+  })
+
+  it('blocks when not PLANNED', async () => {
+    m.idea.findFirst.mockResolvedValueOnce({
+      id: 'idea-1',
+      status: 'PLAN_READY',
+      pbi_id: null,
+    })
+    const r = await relinkIdeaPlanAction('idea-1')
+    expect(r).toMatchObject({ code: 422 })
+  })
+})
+
 describe('downloadIdeaMdAction', () => {
   it('returns grill_md when present', async () => {
     m.idea.findFirst.mockResolvedValueOnce({